Ottawa is facing big questions as its move to legalize cannabis use for adults goes hand in hand with stricter laws on drunk and drugged driving and tough sentences for those providing marijuana to minors.

While the Alberta government is supportive of new measures around roadside tests, a University of Calgary law school professor and a prominent city defence lawyer say many of the new federal laws go too far and will almost certainly be challenged as unconstitutional.

In keeping its campaign promise on legalization, the Liberal government last week unveiled a crackdown on impaired driving that will no longer require police to suspect a driver has alcohol in his or her system to administer a roadside test.